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Source of material 1,3-Dicyclohexyl-1-(tetrahydrothiophene-2-carbonyl)urea was prepared by reacting of thiophene-2-carboxylic acid (0.01 mol) and dicyclohexylcarbodiimide (0.01 mol) in dichloromethane over 24 hours (353 Kt or eflux), followed by aqueous work-up and extraction. The product was crystallized by dissolving the crude material in hot ethanol solution, and slow cooling to the room temperature. Experimental details DiscussionIn recent years, more and more attention has been focused on synthesis and properties of thiophene carboxylic acid derivatives, which not only play an important role in constructing coordination polymers with attractive topological structure but also have been found applications in al arge number of organic reactions and widely employed in organic synthesis and reported to be potential anticancer agents [1][2][3]. Especially thiophene-2-carboxylic acids, such as 3-arylsulfonylamino-5-phenylthiophene-2-carboxylic acid, have been discovered as potent inhibitors of HCV NS5B polymerase and HCV subgenomic RNA replication [4,5]. The bond lengths and angles in the title molecule (figure, top) are within normal ranges. The thiophene ring (C1/C2/C3/C4/ S1) is slightly puckered, with an r.m.s. deviation of 0.019(2) Å.T he four atoms N1, C5, C6 and O1 are coplanar (r.m.s. deviation = 0.028(2) Å,p lane p1) and the atoms N2, C12, C13 and O2 are coplanar (r.m.s. deviation =0.023(1) Å,plane p2). The dihedral angles formed by the thiophene ring with p1 and p2 are 60.7(3)°a nd 43.1(3)°,respectively. The cyclohexyl groups are in achair conformation. It should be noted that the hydrogen bonding interactions plays an important role in the crystal structure of the title compound. As shown in bottom figure, adjacent molecules are linked by intermolecular N2−H2···O2 i (symmetry code i: 2−x, 2-y,−1/2+z)hydrogen bond interactions to form chains stabilizing the crystal structure.

C 28 H 22 N 2 O 6 S 2 ,monoclinic, C12/c1(no. 15), a =22.591(1) Å, b =13.3972(8) Å, c =19.874(1) Å, b =94.018(1)°, V =6000.3 Å 3 , Z =8,Rgt(F) =0.068, wRref(F 2 ) =0.178, T =298 K. N,N-ditosyldibenzo-1,5-diazocane-2,6-dione was prepared by reacting of p-toluenesulfonylchloride (0.01 mol) and as odium carbonate (0.03 mol) solution (40 mL) with 2-aminobenzoic acid (0.01 mol). The pH of the mixture was adjusted to 3after reacting 20 hours at room temperature, and then awhite solid of the title compound was obtained after filtration and column chromatography separation. The purified product was dissolved in 95 %etha-nol and single crystals were separated after 8days. Source of material Experimental detailsAll Hatoms were positioned geometrically and allowed to ride on their parent atoms at distances of d(Csp.96 or 0.97 Å with U iso = 1.5.U eq(parent atom). DiscussionThe sulfonamide family includes abroad-spectrum of synthetic bacteriostatic antibiotics used against most Gram-positive and many Gram-negative microorganisms and protozoa [1]. These compounds are commonly used in human and veterinary medicine for therapeutic and prophylactic purposes to fight common bacterial diseases [2]. Furthermore, in animal husbandry these substances are commonly used for the prevention and treatment of dairy cattle for several infectious diseases, prophylactic, or as feed additives to promote growth in farm animals [3,4]. In the crystal structure of the title compound, no significant differences appear in the bond distances and bond angles comparing to the similiar compounds [5]. The C7-N2 and C8-N1 bond distance [1.388(9) Å and 1.38 (1) . The partial double bond character of the structure is presumed as ar esult of the electron delocalization. The para-substituted phenyl ring shows approximately the expected C 2v symmetry so that for the two matching endocyclic bond angles this holds true even at the 2ο level. Therefore, it may be concluded that the angles at C16 (116.9(8)°), C23 (118.3(8)°)a nd C19 (121.5(8)°), C26 (120.8(7)°)a re significantly diminished and enlarged, respectively. According to the conclusions of Domenicano et al. [8], it follows that the Satom introduces asmall electron-withdrawing effect, whereas the methyl substituent introduces electron-releasing properties. The seven atoms of C1 to C7 and N1 are coplanar (r.m.s. deviation = 0.0241(3) Å,plane p1). Another seven atoms of C8 to C14 and N2 are coplanar with the r.m.s. deviation of 0.0210(3) Å (plane p2). The sulphur atom S1 and the phenyl group C15 to C21 are coplanar (r.m.s. deviation =0 .0317(6) Å,p lane p3). The other sulphur atom S2 and the phenyl group C22 to C28 are coplanar with the r.m.s. deviation of 0.0580(8) Å (plane p4). The dihedral angles formed by the plane p1 and p2, plane p3 and p4 are 76.5(2)°and 64.07°,respectively.

Source of materialPhenylsulfonyl-5-fluorouracil was prepared by reacting 5-fluorouracil (0.01 mol) with triethylamine (0.02 mol) and phenylsulfonyl chloride (0.02 mol) in anhydrous dichloromethane over 12 hours (353 K, reflux), followed by aqueous work-up and extraction. The purified product was dissolved in 95 % ethanol and single crystals were separated after 10 days.

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